two questions - Cycling and Oxygen

[Iam]

Hi everyone..

I've been posting questions about cycling. I am learning more and more but I still have questions..

Tank 30g About 4 months old
(seahorses only (6))
No skimmer
211 powerhead
2 Biowheel filter

Amonia - 0
Nitrite - 0
nitrate - 15 (and getting higher if I don't change some of the water)

question: why nitrate rises even though the amonia and nitrite are 0

and the O2 level.. I just got one of those tests.. and I guess my O2 is about 4..I read in a book that it should be around 7
is that true? and what can I do to increase it?

Thank you guys...

 

[meco65]

get a power head and point it at the serfice of the water to agitate it more or a air stone. But the air stone can cause salt creep.

 

[TekCat]

your fish (seahorses) produce constantly waste, that in turn makes ammonia, followed by nitrite and nitrate. The reason that your test shows zero is because bacteria chews up ammonia and nitrites very quickly and efficiently. Nitrates on the other hand keep accumulating in your tank and need to be exported via water changes, growing macro algae, etc....

Another observation, instead of bio-filter (which will in time become nitrate factory) have at least 30lbs of LR in tank.


As far as O2 goes, there are few things you could do to
you could add skimmer (highly recommended); if you have a lid on your tank - remove it, in addition using a powerhead poiting toward the water surface increase surface agitation. THis all helps gas exchange.

 

[Amphiprion]

TekCat is right on here. Minaralization (or Nitrification, if you prefer) is a very efficient process, so many of the levels of ammonia and nitrite are undetectable using conventional means. However, as in any tank, they are always there and there is a small amount of both in solution at all times. The powerhead and protein skimmer are a good start for oxygen production, but will vary on the oxygen availability in your home. Refugia with macroalgae, combined with good aeration (from a skimmer, powerhead, etc) will ensure there is good oxygen and will prevent any supersaturation issues (especially with seahorses).

 

[Iam]

Thank you guys..
Sorry I didn;t mention it earlier...I have about 35lbs LR
I just added the powerhead.. so I guess I am on my way to skimmer..
one more thing... for the 30g tank... (and I use RODI ) is it okay the change 5g every week?

 

[TekCat]

with 35 LR you don't really need bio-wheel.
- 5G every week is fine, you could get away with 3g per week (10%) but 5G is definatelly better.

Good job

 

[Iam]

Hey TekCat..
Ok i'll do 5g...

Does anyone change water 10% every week?
is there a way so that I don't have to change water? (don't get me wrong I am not leasy, just curious)
I've been reading about sumps... do you still change water even if you have a sump..

 

[TekCat]

I am doint 10% on my 55G, that is 5G every week.
Yes you need to do water changes regardless if you have sump or not. There are 2 major reasons for that: First you export nitrates, toxins, and other boilogical products. Second, seawater elements get depleted overtime, for example coraline algae takes calcium, alk, magnesium, etc..... so, these chemical elements need to be refilled either by water change (of fresh salt mix) or dosing. Water changes IMO are easier

 

[Iam]

thank you so much TekCat
I thought something was really wrong with my tanks (30g) (60g)
because if I don;t change the water nitrates go high,.. And I thought skimmer could prevent that (my60g has a skimmer)
but it's great to hear that everybody does (or atleast should) change water..
thanks a lot

 

[bertoni]

4 ppm is rather low. My tank reads 7. I agree that a skimmer would be a fine addition. More flow might help, too, but I don't know how well the seahorses would adapt. You might want to check in the specialty forum:

http://www.reefcentral.com/forums/forumdisplay.php?s=&forumid=35